File:John Loudon McAdam, 1830, National Gallery, London.JPG|thumb|John Loudon McAdam, 1830, National Gallery, London
'''John Loudon McAdam''' (born '''John Lowdon McAdam''', 23 September 1756
[macadamisation", for building roads with a smooth hard surface, using controlled materials of mixed particle size and predetermined structure, that would be more durable and less muddy than soil-based tracks.
Modern road construction still reflects McAdam's influence. Of subsequent improvements, the most significant was the introduction of tar (originally coal tar) to bind the road surface's stones together, "tarmac" (for Tar Macadam.) ]